Turning down a bbl

[Ironworker]

In my 6.5 PRC I have a 28"Bartlein heavy varmint. Can this bbl be turned down to Remington varmint contour with out sacrificing accuracy?

 

[BoydAllen]

Yes, I believe that it can, but I would take light cuts. Generally, it is button barrels that you have to be careful about reprofiling, because of the risk that they might have some residual stress that would cause the cut down areas to slightly expand their bores. The cut rifling process does not put that stress into a barrel.

 

[paperpuncher]

I would say yes I have done it without No I’ll effect. That being said it is a pia and it will require some experiments with speed feed and tool geometry. It’s the kinda thing that everybody should do at least once

 

[tobnpr]

It’s the kinda thing that everybody should do at least once

And after you do it once, you'll never want to do it again

 

[skeeljc]

Just find someone with a CNC lathe to do it.

 

[Dusty Stevens]

They need to have a hydraulic follow rest to not start drinking

 

[Sniperhandle]

You used to be able to send a barrel in to McGowen and they would re-contour the barrel for you, They wanted to know the maker and would charge $60.00, This was around 10 years ago, I don't know if they still do it, Most of them are too busy to mess with this nowadays, You might check with Douglas as well, Ask Stan on here if they do it.

 

[Dusty Stevens]

You used to be able to send a barrel in to McGowen and they would re-contour the barrel for you, They wanted to know the maker and would charge $60.00, This was around 10 years ago, I don't know if they still do it, Most of them are too busy to mess with this nowadays, You might check with Douglas as well, Ask Stan on here if they do it.

Douglas will only do theirs and Stan is no longer with us.

 

[INTJ]

Stan is sadly no longer with us. But I agree, a recontour should be done by someone with dedicated barrel contour equipment. After just having been through this, even with a CNC shop there is no guarantee as to results.

The barrel the CNC shop recontoured looked great until I dialed it in. There was .011" runout on the outside when the bore was dialed to less than .0001".

 

[hogpatrol]

I know of one vendor that will recontour and only one size down with no guarantees on post turning accuracy.

 

[Dusty Stevens]

Stan is sadly no longer with us. But I agree, a recontour should be done by someone with dedicated barrel contour equipment. After just having been through this, even with a CNC shop there is no guarantee as to results.

My CNC shop recontoured barrel look great until I dialed it in. There was .011" runout on the outside when the bore was dialed to less than .0001".

Think of how it was in the middle

 

[Sniperhandle]

Douglas will only do theirs and Stan is no longer with us.

Oh man, I am really saddened by this news, Total Bummer?

 

[Dusty Stevens]

Oh man, I am really saddened by this news, Total Bummer?

Yes it is a total bummer.

 

[Ironworker]

Will Bartlein turn down one of their bbls? My gunsmith said for him to do it, it would be cheaper to buy a new bbl—$ 400 for a new bbl and chamber and fit, nearly a thousand bucks.

 

[urbanrifleman]

Dang. I'm not charging enough.

 

[LVLAaron]

Dang. I'm not charging enough.

I think it's one of those things like "I dont want to do it but I'll do it if you pay me too much"

I've turned exactly one barrel down. Heavy Varmint down to 1 inch straight and 875 or whatever it is for an AR gas block. that's enough for me.

 

[urbanrifleman]

I think it's one of those things like "I dont want to do it but I'll do it if you pay me too much"

I've turned exactly one barrel down. Heavy Varmint down to 1 inch straight and 875 or whatever it is for an AR gas block. that's enough for me.

I turn them almost every day I am in the shop. During COVID I was forced to learn as I could not get contours.

Lots of crazy stories about contouring out there.

PS: I am not a contouring shop.... but I contour whenver I need too for my OWN uses. I am not sure what the big deal is about it.

 

[urbanrifleman]

PSS: Gunsmithing lathes suck for contouring. Too small. Too light.

 

[shortgrass]

Will Bartlein turn down one of their bbls? My gunsmith said for him to do it, it would be cheaper to buy a new bbl—$ 400 for a new bbl and chamber and fit, nearly a thousand bucks.

Sometimes people won't listen to ya'. When they won't, the best way to teach 'um is through their wallet! Then they might get the picture. Turn a barrel to another contour on a 13-14"manual gunsmithing lathe, and you've gotta' stand right there all the while it's cutting. Turn a barrel to another contour on a properly equipped CNC and you can step back and do something else while it's cutting. Sure, you have to pay attention to it, but it's not nearly the same situation. It'll take multiple passes, there's not a man alive that can reset for the next pass as quickly as that stepper motor when it's "in it's rapids", say at 400+ inches per minute.......